Late last year, a spike in robberies in Capitol Hill’s historic center was attributed in part to robbers ripping cellphones from people’s hands. After a community meeting with residents and police, the department sent in reinforcements, boosting its presence and making more arrests around Eastern Market and the nearby Metro stop.

The recent rash of robberies is similar to the snatch-and-grabs that occurred late last year, most between 6 p.m. and 1 a.m., 1st District police Cmdr. Daniel P. Hickson said at a Monday news conference.

But Saturday’s attack — in which 29-year-old solar-energy analyst Thomas C. Maslin was beaten in the head and found on a front porch three doors from the home of a U.S. senator — stands out for its intensity.

Police say they have not determined whether Maslin was robbed. Hickson said three robberies in the area this month were violent, involving punches to the face, but “nothing remotely like what happened Saturday.”

That has stoked fears in the Southeast neighborhood near the U.S. Capitol.

“The brazenness of some of these attacks, and the number that include handguns, are disconcerting,” said Ivan Frishberg, who heads the area’s Advisory Neighborhood Commission.

“There’s a sense in this community that there is something going on, but we don’t know what it is yet,” Frishberg said. “This incident has really shined a light on the issue because of the severity of the injuries the victim suffered.”

Robberies, armed and unarmed, are up in central Capitol Hill this year. According to police statistics, there were 56 through Sunday, up from 36 for the same period a year ago. Although far more infrequent, armed assaults are also up.

District police say 19 people have been robbed, two at gunpoint, since July 1 in the police service area that includes Eastern Market. Hickson said he is working on instituting more patrols and other measures to address the problem.

District police have released few details on the assault on Maslin, who on Monday remained hospitalized in critical condition. His wife, Abigail Maslin, 30, said he has undergone two surgeries to relieve pressure on his brain.

“I think this is an hour-to-hour situation,” Maslin said, adding that her husband is “fighting right now” to stay alive. After emerging from the operating room Monday, he could move a bit and squeeze her hand, she said.

“The first day of this was an absolute nightmare,” said Maslin, a teacher at Brent Elementary School on Capitol Hill.

Maslin said her husband attended the Nationals game Friday night with a friend who is moving to Africa. They then went to the Tune Inn tavern on Capitol Hill. Maslin said she assumed her husband slept over at a friend’s when he did not come home.

By 10:30 a.m. Saturday, with no sign of her husband, she filed a missing-persons report with police — not knowing that two hours earlier and seven blocks from her home, a pedestrian walking in the 700 block of North Carolina Avenue called 911 after seeing a man on a porch who appeared to be suffering a seizure.

Paramedics took the man to the hospital, where police said a doctor discovered he had been hit on the head with a blunt object. Maslin said a doctor at the hospital who is a family friend called to tell her that her husband was there.

Hickson said that the last confirmed sighting of Thomas Maslin before the attack was at 12:30 a.m., though he would not say where, and that police did not know what happened between that time and the time he was found eight hours later.

A man who lives next door to where Maslin was found said Saturday that detectives told him that Maslin might have been beaten in a nearby, wedge-shaped park and may have stumbled from door to door seeking help without success.

Police have not released information about any suspect. Hickson said detectives could not corroborate that Maslin had sought help, and he would not comment on whether the park between North Carolina and Independence avenues was the crime scene.

D.C. Council member Tommy Wells (D-Ward 6) called last year’s community meeting and said police did a good job addressing residents’ concerns at that time. He said he has been back in contact with city police after the recent outbreak of robberies and assaults. “We’ve been assured more police officers,” Wells said. People are particularly vulnerable when they are walking home alone after bars close, he said, but “any crime is unacceptable.”